The folks at the Tasmanian Museum are regional specialists and had made the natural assumption that the starfish they were seeing were morphological varieties of their local species, Uniophora granifera, which looks like this:

Eventually, the began to see more and MORE of these. The coloration was thought to be part of the natural color variation in Uniophora. But eventually, there were more and more specimens and they realized something was....off. They brought specimens of the animal to the South Australian Museum.

It turned out NOT to be Uniophora, but the North Pacific species, Asterias amurensis!The invaders had arrived!

This was evidently quite a shock! The news was announced directly via the Australian Broadcasting Channel in 1992 and to quote Elizabeth Turner at the Tasmanian Museum:
"Suddenly all hell broke loose. The media and public could not hear enough about it."

This was unprecedented!! To suddenly have discovered a VERY prominent marine predator in their midst with potential menace to a multi-million dollar aquaculture industry. Plus, these animals occurred in large numbers..so unlike, say tunicates, you could SEE these lovely yellow and purple beauties all over the place.Reaction & Response So, all of the various Australian marine organizations got to working! And to make a long story short, the various organizations, such as CSIRO and the Department of Primary Industries and Fisheries had formed the National Seastar Task Force! (on a personal note- I have only seen the words "sea star" -"starfish" and "task force" used together EVER, TWICE. Both times in Australia! AWESOME!)

Information was disseminated! but this was just as the Internet was forming..so we saw Pamphlets! Posters! The word was out!

They organized a "clean up" of A. amurensis from an area off Prices Wharf in the Hobart area.

This clean up resulted in SIX THOUSAND specimens being collected from a 300 meter stage. Subsequent dives resulted in 24,000 animals killed and piled on the wharf.

I should make sure to note, this did almost NOTHING to the population !!!

What do you do with 30,0000 dead starfish?? These were sent off to composting by the University of Tasmania!

So Where Did They Come From???
Funding started to flow towards various universities and labs to get data on the introduced pest. So, the invaders had arrived via ballast water on ships-but from WHERE??Early allozyme work using genetic distances (different from today's population genetics using gene data) narrowed down the populations from Tasmania as being most similar to populations in Japan (near Tokyo and Suruga).

Repel the Invasion??Various methods of minimizing the impact of this species have been developed, considered, and studied over the years. Some are used today and others were not. This includes:

1. Using DNA "fingerprinting"to recognize the larvae from ballast water. Such as in this paper.2. Various poisons, such as the classic anti-starfish measure quicklime, formalin, ammonia, copper sulfate, and even reproductive inhibitors!! The list goes on. Unfortunately all seem to be just as harmful to humans. So, not ideal and let's say...NOT a primary strategy.3. Natural Control. There are ciliates that parasitize and can castrate sea stars in the North Pacific. This was considered...but using introduced species Vs. introduced species is usually a way to exponentially INCREASE your problems. Its not clear that these could distinguish between A. amurensis and Australian species. So..uh...maybe not.

4. ....and the old standby, physical removal! Simply put-pullin' them off and throwin them up on the pier. Interestingly, there was also a discussion of using A. amurensis in "commercial harvesting".Apparently, they cost $1.00 USD in China for FOOD. ugh...(allegedly they are tasty steamed-yuck) They concluded there was NO market for human consumption.

Good call.What has been the Impact??
So, its now 2009 and its been 23 years since A. amurensis has been in Australia! What has changed???1. Range Extension. A. amurensis has SPREAD from Tasmania to the southern part of Australia! New Zealand is on alert...2. The Impact on Soft-bottom communities.A lot of ecological work has been funded since A. amurensis has taken hold. A lot of this work has been done by Dr. Jeff Ross at the University of Tasmania.

They eat a variety of bivalves, including the commercial bivalve Fulvia tenuicostata, various snails, and the sea urchin Echinocardium cordatum, changing the abundance of these animals and the long-term ecology of soft bottoms.The Carcinus-Asterias ONE-TWO PUNCH! Also, it turns out there's MORE then one big introduced predator in Australian waters!

There is apparently competition between these crabs and Asterias in the feeding of these beasts on bivalves. Asterias amurensis apparently feeds on the BIG bivalve prey VERSUS the crab, Carcinus maenas which feeds on the small ones!! Consider this as there's more and MORE of these and as the two species begin to impact all of the bivalves in the region.

yow.

So, what's the lesson here? Hmmm... Introduced species-BAD.

In contrast an invasion of starfish from space seems kind of welcome...

But the short version is that introduced species are those which are not endemic (i.e., brought from outside its natural range) that have unanticipated ecological effects that have deleterious (=bad) economic, agricultural or other environmental impacts.

Above are examples of different introduced marine species to the North Pacific of Canada (among other places). Basically different marine invertebrates that have been spread via various ways to areas WAY outside their natural range. Once introduced they have NO natural ties to the ecosystem to their new home.

No Predators. No close ecological relationship with prey. So, they go crazy and cause all kinds of problems!

To illustrate this point quickly..Think of the human equivalent of an alien invasive....Obviously, one is pretty bad..but more then one and running around on Earth? NOT good.

Marine introduced species are brought along and introduced via a variety of ways. But one of the most prevalent ways?? Boat Ballast Water.

Basically, the larvae (i.e., the babies) of various invertebrate animals are picked up from their natural range, carried around the world where the ship goes and then offloads and dumps them into the water!! Here is the larval stage of our subject today....

But here's the thing, a lot of these invertebrates usually have some kind of physiological predisposition for survival. They can usually tolerate wide ranges of salinity, temperature, and etc. They don't always survive for long where they get dumped off.

Why are echinoderms so unusual as introductions??

Echinoderms are usually pretty sensitive to where they live (since they are essentially filled with seawater). They generally don't tolerate freshwater (I have often seen many dead starfish following a lot of rain in California) and echinoderms are pretty fickle when it comes to temperature, water quality, and etc.

So, generally echinoderms are NOT seen as introduced species in the best-known sense. But then, one found a niche....

MEET Asterias amurensis....A. amurensis occurs naturally in the sub-Arctic North Pacific, including the Aleutian Islands/Alaska, Japan, Russia and thereabouts. Mostly in shallow-water but can occur down to about 200 meters depth.So, this species was essentially transported from the other side of the world!! And miraculously found itself in the cool, temperate waters of Tasmania and South Australia. In an environment VERY similar to its natural range!

A. amurensis is known for two things which makes for a GRAVE concern to Australia.

1. A. amurensis is VERY fecund. A single female of this species can produce 20 MILLION eggs! Since discovery in the early 90s, this has translated to an estimated 30 MILLION individuals in Tasmanian waters (mostly in the Derwent estuary).2. They EAT shellfish. A LOT of them.

Australia has a number of very successful shellfish (i.e., bivalves) fisheries. Cockles, mussels, scallops. etc. So, a great deal of work has been dedicated towards the study of the ecological impacts.

Among the more significant findings is this study by Hudson et al. that the introduced A. amurensis does NOT induce the natural escape response that the endemic species does! So, the natural ecological behavior to "RUN AWAY" that endemic Australian starfish species have co-evolved with various scallops is absent from the interaction between the introduced A. amurensis when it feeds on Australian scallops!!

So, in honor of SDCC and a recent storyline featuring Starro, here I compare the character VS the REALITY!

Are they SO different?? yes-one lives in space and true starfish do not. But consider this:

1. The new Starro (from R.E.B.E.L.S. annual #1) has this fearsome new look!An interesting mesh of several possible living species!

The body, for example, is CLEARLY from the family Asteriidae. Such as this specimen of Pisaster ochraceus from the west coast of North America.

Starro clearly has adambulacral spines, an actinal surface and even a set of marginal plates around the ventrolateral edge.Even MORE interesting-Starro has TEETH! Yes, the ones in the middle of the arm are most noticeable..but if you look on the angles pointing into the mouth?? With the spines directed orally??/

REAL starfish have these also!!Some such as this odontasterid (Acodontaster) have one big teeth projecting out from the mouth.Some starfish have TWO spines around the mouth!!! The name of this beast-Diplodontias-LITERALLY means "two teeth". "Diplo"= two and "odontos"=teeth!Some beasts, such as this specimen of Pteraster gibber have teeth with clear, hyaline tips (in red circles)!!....and just to be thorough...some brittle stars have something similar-they also have "teeth" that project into the mouth!2. The Old Starro did the mind-control thing by grabbing onto the face and voila! Instant zombies!....and who among starfish enthusiasts does not have slavish devotion to their subjects??Have a great weekend!

1. How are these Japanese names decided??
There are no strict rules for these names but apparently, there is a long tradition for the use of certain names. According to Dr. Kogure:

...most of the Japanese common names have been proposed in encyclopedias or picture books. In fact, we can see some wood prints of starfishes with common names in the encyclopedia published in the Edo period. The attached picture is the sea star and sand dollar in the encyclopedia published by Ryoan Terajima, a Japanese medical doctor in the Edo period, in 1712.

Wow!!! LOOK at that!! Astropectinids recognized from 1712!!!! I'll have to check but this might one of the OLDEST recognized names of starfish!!

2. What is the difference between momiji and hitode???

So, we now have TWO Japanese words for "starfish". Hitode and momiji.

For example this species (Ctenophoraster diploctenius) has the Japanese name: udenaga-kagitoge hitode

It turns out thatmomijitranslates to "maple leaves tinged with bright red" and is the Japanese word for "astropectinid (or at least astropectinid-like) starfish"!!! The name apparently refers to starfish with this particular body form.To quote Dr. Kogure:

The name momiji is short for momiji-hitode or momoji-gai. As you know, hitode is the most common use of the Japanese word to indicate sea stars. The word gai or kai means shellfish in Japanese. Our remote ancestors considered that the sea star was one of the groups of seashells. The Japanese common names of sea stars have hitode in most of the species, or momiji in some groups. For example, we can see the word momiji in some astropectinid sea stars and goniasterid sea stars such as Pseudarchaster parelii (aka-momiji: red sea star).

3. Examples!
Below is Ctenopleura ludwigi, whose Japanese common name is oh-nise-momiji.

Ohtranslates to "large" and nisetranslates to "pseudo"...so the "Large fake astropectinid" which possibly reflects its superficial resemblance to Astropecten.

(all starfish photos by Yoichi Kogure)

This Japanese species-Astropecten latespinosus has a pretty well flattened body. Japanese name ishira momiji. Hira means "flat"..so "Flat astropectinid" (to contrast-the latin latespinosus refers to the lateral fringe of spines around the edge of the body)

..and the related Leptychaster arcticus?? Japanese name is kita-usu-momijiKitarefers to "northern"(L. arcticus is a species that lives in an Arctic/subArctic band) and follows the Leptychaster formatfor "thin" = usu

HUGE thanks to Dr. Yoichi Kogure for his help and information that contributed to this post!

About Me

I pursue starfish related adventure around the world with a critical eye and an appreciation for weirdness.
Support has been courtesy of the National Science Foundation but the views and opinions presented herein are mine and do not reflect the opinions of them or any affiliated institutions.
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